If $x$ men can do a piece of work in $x$ days,then the number of days in which $y$ men can do the same work is (in days)

$A$ is thrice as good a workman as $B$ and therefore is able to finish a job in $60\, days$ less than $B.$ Working together,they can do it in (in $days$)

If $A$ and $B$ together can complete a work in $18$ days,$A$ and $C$ together in $12$ days,and $B$ and $C$ together in $9$ days,then $B$ alone can do the work in (in days)

$P$ and $Q$ can do a piece of work in $30$ and $40$ days respectively. They began the work together,but $P$ left after some days and $Q$ finished the remaining work in $12$ days. After how many days did $P$ leave?

Heena can do a work in $20$ days,while Himani can do the same work in $25$ days. They started the work jointly. $A$ few days later,Mayuri also joined them,and thus all of them completed the whole work in $10$ days. All of them were paid a total of $Rs. 700$. What is the share of Mayuri (in $Rs.$)?

$A$ and $B$ can do a work in $8$ days,$B$ and $C$ can do the same work in $12$ days. $A, B$ and $C$ together can finish it in $6$ days. $A$ and $C$ together will do it in (in days):